Healthy phalaenopsis orchids but no spikes or blooms! What am I doing wrong??

[Orchid grower]

Originally Posted by Ray

You are not looking for a 10-degree drop in nighttime temperature (that's Celsius, equivalent to 16 degrees Fahrenheit), you are looking for about two weeks of an average reduction in growing temperature of that much. A ten degree nighttime drop is only a five degree drop in the average.

Then it takes about six to eight weeks for a spike to emerge.

So what temperatures are your plants exposed to without use of the heat mat? I'll bet you're growing them too cold.

Also, don't be in a rush to add more fertilizer or change formulas. That's not going to fix anything.

Thank you so much for your response!

I just started using a thermostat yesterday and it said that last night the lowest was 12 degrees celcius and today the highest 22 celcius. However the weather has just started to warm up this past week and I think they would have been growing in colder temps the past couple months.

If you do not mind could you please explain the first bit of what you were mentioning again- that I'm not looking for a drop in temp but an average reduction in growing temp?

I mention the fertilizer because currently I was using "growmores" 20-10-20 urea free orchid fertilizer but I've come across conflicting information regarding the urea - that it may not be as bad for phals as I thought it was. I also have the same brands 20-20-20 orchid fertilizer but it's not urea free so I wasnt using it. I've read the middle number is good for encouraging blooms so I thought it might be a good idea to start incorporating it.

Thanks again!

---------- Post added at 10:25 PM ---------- Previous post was at 10:09 PM ----------

Originally Posted by Roberta

indeed, duration of light is more important than intensity. I had success with supplemental light (the cheapest fluorescent lights that I could find) on a timer 12 hours a day. Even in California, I found that light coming in the window by itself was not sufficient - maybe 4 hours of good east light, then the sun shifted and it was indirect. With those lights I went from hardly any reblooming to about 80% reblooming. It works!

Wow that's a big difference in reblooms! I think insufficient light really might be the problem.. or one of the problems. There were definitely days where the blinds remained closed all day to keep the cold out.. That is all changing now with the weather warming up and the sun finally coming out.

If I were to add some additional lights would something like this style work? Would this work in addition to having the blinds open? Thanks!

Lovebay Timing Function Dual Head Grow Light 36 LED 4 Dimmable Levels Grow Lamp Bulbs with Adjustable 360 Degree Gooseneck for Indoor Plants Hydroponics Greenhouse Gardening [2018 Upgraded] Lovebay Timing Function Dual Head Grow Light 36 LED 4 Dimmable Levels Grow Lamp Bulbs with Adjustable 360 Degree Gooseneck for Indoor Plants Hydroponics Greenhouse Gardening [2018 Upgraded]: Amazon.ca: Patio, Lawn & Garden

[Roberta]

I'll let others speak to the specific lights... I got $9,99 shop lights from Home Depot with daylight tubes (back in the day, before LEDs were available) I tested one bank of grow light bulbs, and was never able to see any difference in performance relative to the cheapies. I was getting some natural light - plants that receive none might benefit more from grow lights. For the record, I didn't have any significant temperature drop - the house was a bit cooler at night in winter, but never went below about 65 deg F (17-18 deg C.), highs maybe 68-70 deg F (20-21 deg C). Commercial growers use a controlled temperature drop for a couple of weeks to inspire timed blooming since the orchid that blooms a week before Christmas or Mother's Day is worth a lot more than one that blooms a week after. As a hobby grower, I'll take flowers any time the plant decides to produce them.

[Ray]

Originally Posted by Orchid grower

I just started using a thermostat yesterday and it said that last night the lowest was 12 degrees celcius and today the highest 22 celcius. However the weather has just started to warm up this past week and I think they would have been growing in colder temps the past couple months.

Personally, I'd never let a phalaenopsis see lower than about 18°C. They grow much better if kept very warm.

If you do not mind could you please explain the first bit of what you were mentioning again- that I'm not looking for a drop in temp but an average reduction in growing temp?

If you grew your orchids at a constant 30°C day and night (thermal cycling is not all that important for phals), then you would want them to be grown for about two weeks at 20°C to reliably induce spiking. If they were grown at 35° days and 25° nights, that's an average growing temperature of 30°, so you'd have to lower that average to about 20° for the same result.

I mention the fertilizer because currently I was using "growmores" 20-10-20 urea free orchid fertilizer but I've come across conflicting information regarding the urea - that it may not be as bad for phals as I thought it was. I also have the same brands 20-20-20 orchid fertilizer but it's not urea free so I wasnt using it. I've read the middle number is good for encouraging blooms so I thought it might be a good idea to start incorporating it.

There is nothing "bad" about using a urea-based fertilizer on your orchids; they simply will not use it as efficiently as they would a nitrate and/or ammonium-based one.

Phosphorus does NOT "encourage" blooms. Read this.

I'm going to go "Bill Nye" on you and disagree with something Roberta said: light duration and intensity are BOTH important.

A plant has to absorb "so many" photons to live, grow and bloom. They are very much like Goldilocks, though - not too much and not too little - and it varies by type of plant.

A light source puts out a certain amount of photons per unit time, and a more intense source puts out more than a less-intense one. Intensity x time = total, so a lower-intensity light source will require more time to reach the same total than a higher intensity light source would.

Obviously there are limits to both - too intense of a light source and you'll burn the plants, and at the other end, too long at a low intensity (even with the total being correct) is not good either, as plants need some "dark time" for other chemical processes to occur.

[Arizona Jeanie]

Here is a link to the grow light I have:
Amazon.com: Hydrofarm JSV2 2' Jump Start Grow Light System: Gateway
It's a 2 ft Hydrofarm (or Jumpstart) with a t5 bulb. Replacement bulbs are easy to find. I didn't see the 2 ft one on Amazon Canada, but you could probably find it somewhere. I have it set up with a programmable timer.
The light you linked to has to be manually turned on and the timer length chosen each day. I had a similar LED light for awhile, the plug fell apart within a year and I threw the whole thing out. Also, the clamp was not a good fit for the table I have. I'm much happier with the stand. I think you'd find it a lot easier to just have an automatic programmable timer. Once it's set, you don't even have to be home for it to work.
The Hydrofarm light does take a little more room, cost a little more, but is stable, adjustable, is easy to use and has held up well.
I think that almost any sort of supplemental light would be helpful, put since you asked...

[Orchid grower]

Thank you everyone for all of your responses and amazing advice!! I truly appreciate it and love that a community like this exists!

[Orchid grower]

Originally Posted by Ray

Personally, I'd never let a phalaenopsis see lower than about 18°C. They grow much better if kept very warm.

If you grew your orchids at a constant 30°C day and night (thermal cycling is not all that important for phals), then you would want them to be grown for about two weeks at 20°C to reliably induce spiking. If they were grown at 35° days and 25° nights, that's an average growing temperature of 30°, so you'd have to lower that average to about 20° for the same result.

There is nothing "bad" about using a urea-based fertilizer on your orchids; they simply will not use it as efficiently as they would a nitrate and/or ammonium-based one.

Phosphorus does NOT "encourage" blooms. Read this.

I'm going to go "Bill Nye" on you and disagree with something Roberta said: light duration and intensity are BOTH important.

A plant has to absorb "so many" photons to live, grow and bloom. They are very much like Goldilocks, though - not too much and not too little - and it varies by type of plant.

A light source puts out a certain amount of photons per unit time, and a more intense source puts out more than a less-intense one. Intensity x time = total, so a lower-intensity light source will require more time to reach the same total than a higher intensity light source would.

Obviously there are limits to both - too intense of a light source and you'll burn the plants, and at the other end, too long at a low intensity (even with the total being correct) is not good either, as plants need some "dark time" for other chemical processes to occur.

Thanks for your thorough reply and the great link! There seems to be alot of good info there.

[Pippa]

Were your plants bought new & were they in bloom when you bought them? I sometimes find it takes up to two years for phals to rebloom after purchase, especially if they were 'rescues' which most of mine are. I bought one which had only 1 2-inch root on it (it was 50p, so I thought it was worth a risk) and it's only just starting to produce a spike now after 2 years and I don't think it will be a very spectacular one. Sometimes if they have been forced into bloom or neglected in the store, they take a long time to recover.

I've also found that phals which stay in bloom for an excessively long time can take longer than a year to rebloom for me - I have one last summer which is now in its 10th month of blooming and barring accidents will probably last a year, judging by the buds left to open - it wouldn't surprise me if it takes more than a year post-blooming to bring this one back into flower!

[twinkie]

Originally Posted by Ray

Obviously there are limits to both - too intense of a light source and you'll burn the plants, and at the other end, too long at a low intensity (even with the total being correct) is not good either, as plants need some "dark time" for other chemical processes to occur.

What do you think the magic number is for 'dark time'? I've heard 12 hours, but most nights I'm up working and the phals are up too. They might get 6 hours dark during Winter and even then my skylight is overhead open to moonlit skies. This is a subject I'm interested in as all of my phals save two are constantly blooming. I use a simple goose neck lamp with a 9 watt led full spectrum bulb and two short full spectrum tube lights besides East and South facing positions for natural light coming in. I'm in the very dark Pacific Northwest where days are very short and dark in Winter. I've only now started turning off the lights around 11 p.m. after being on for 12, add to that number natural morning light now coming in for around 3 hours before the light gets turned on. I always thought that if they're blooming they are happy, always new leaf growth and root growth too, but could I be overdoing the light??

[Roberta]

If they are blooming, don't argue with success... I doubt that the moonlight has much effect. And Phals aren't all that picky about the amount of dark they get as long as they get some. (Some Catts are more sensitive) But if they bloom, you clearly are giving them what they need. That's the goal!

[twinkie]

Originally Posted by Roberta

If they are blooming, don't argue with success... I doubt that the moonlight has much effect. And Phals aren't all that picky about the amount of dark they get as long as they get some. (Some Catts are more sensitive) But if they bloom, you clearly are giving them what they need. That's the goal!

Hey thank you for that! I've been hitting the midnight oil heavy and was starting to worry as I'd forget to turn off the grow lights til even 3 a.m. I have to admit I've been putting a paper over the glowing blue sound system light at night that shines into their space and turn off the printer too lol have been worrying over light lately. I'm sure all plants need some kind of rest, I don't want to exhaust the poor things if am artificially inducing too many blooms heeheh #selfish